1. Field of the Invention
In some embodiments this invention relates to medical devices, such as catheter systems of all types, as well as their manufacture and assembly. Some embodiments are directed more specifically to bifurcated balloon catheters, and the methods and mechanisms directed to their manufacture and preparation for use.
2. Description of the Related Art
Atherosclerotic cardiovascular disease is common, and is caused by a narrowing of the arterial lining due to atherosclerotic plaques. Medical balloons are used in the body in the treatment of atherosclerotic cardiovascular disease and include dilatation devices, typically balloons for example, for dilating stenotic regions of an artery or other vessel, and/or for expanding prosthetic devices such as stents at a desired location therein.
Within the vasculature, it is not uncommon for stenoses to form at a vessel bifurcation. A bifurcation is an area of the vasculature or other portion of the body where a first (or parent) vessel is bifurcated into two or more branch vessels. Where a stenotic lesion or lesions form at such a bifurcation, the lesion(s) can affect only one of the vessels (i.e., either of the branch vessels or the parent vessel) two of the vessels, or all three vessels.
Some balloon catheters intended for use at vessel bifurcations may include auxiliary portions, such as an auxiliary inflation balloon. Such balloon catheters may be utilized to dilate the region of the lesion, such as in a balloon angioplasty procedure and/or are used to deliver and expand specialized stents that have dedicated side branch structures, wherein the auxiliary portions are used to achieve proper expansion of the stent's side branch structure. Some examples of bifurcated balloon catheters equipped with auxiliary or side branch balloons, and/or examples of stents having specialized side branch structures are found in: U.S. Pat. Nos. 6,210,429; 6,835,203; and 7,220,275, the entire contents of each being incorporated herein by reference.
Because it is typically necessary for balloon catheters of all types to traverse a tortuous anatomy as they are being advanced through one or more bodily vessels; it is desirable for the balloon to assume as low a profile, i.e. the outer diameter of the balloon, as possible. Considerable effort has been put forth in the development of dilatation balloons with a low profile by minimizing the dimensions of the core or the inner tube which extends through the balloon to its distal end, and by reducing the wall thickness of the balloon itself.
One way to achieve a low profile of the balloon is by folding the balloon to form a number of wings, which are then wrapped about the catheter shaft. Prior to use, the balloon is typically folded or wrapped about the balloon catheter to fit within and pass through a lumen of a guide catheter sized for insertion into the appropriate vessel or body lumen of the patient. When inflation fluid is applied to the deflated balloon, the balloon wings or flaps unwrap and the balloon inflates to a fully expanded condition.
Various techniques or balloon constructions have been employed to facilitate the folding of the balloon about the balloon catheter in a uniform manner upon evacuation and deflation of the balloon after use.
In the case of bifurcated balloon catheter systems employing an auxiliary or secondary balloon, the secondary balloon further increases the profile of the catheter system, thus affecting flexibility and deliverability of the system. The reduction and assembly of such bifurcated balloon catheter systems can also be significantly more time consuming than standard balloon catheters.
There remains a need for specialized preparation of suitable catheter systems in order to provide a compact, low profile delivery device, and which provides both the primary balloon and secondary balloon with a folded configuration that is efficiently achieved.
The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §1.56(a) exists.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.